An immortal glowing humanoid, with light at 500 lux, who surveys sapient forms of life, such as humanity, based on the actions that the majority of the entire race takes. The humanoid produces orbs of light which are able to inform him telepathically by the orbs own vision (the humanoid sees what the orb of light sees) in order to survey multiple areas at once.

However immortal, the entity has limits, as the orbs of light can be contained in a mirror box, where the light being emitted constantly reflects off the mirror, leaving the humanoid entity seeing just light, as the orb of light only sees light. There is no exact reason as to why the entity surveys life, or what it expects to see as it is surveying. The entity uses its vast celestial knowledge to better keep watch of possible sapient life forms, which leads to the theory of extraterrestrial life.

First, humanoids SCP objects are tricky to write for various reasons, including Mary-Sueism and inserts (not saying at all that I think that's what's going on here, but it does happen). Why does it tak the form of a 'humanoid'? Why not something…else? If it's immortal, and glowing, it already surely would draw enough attention to itself - though I know you haven't included how this object is viewed yet - without also being in a humanoid shape. You may have read it already, but this guide can be helpful if you want to stick with the humanoid theme - http://www.scp-wiki.net/so-you-want-to-write-a-humanoid-scp-object

Secondly, although I see you're trying to connect it more to the idea of extraterrestrial life, the base idea comes off very much as 'A God am I', which The Foundation already have various types of at various levels. The idea of anything watching over humanity is going to summon up thoughts of a 'God'-like creature before the idea of an alien-like creature (in my opinion - I'm sure it can be written to good effect with more details and research). I think if you had a good story behind it that put more focus on the idea of it being alien, and actually why it chooses to look over humanity (research, curiosity, tourism?) and maybe chose a different form to 'humanoid', you might have something with some more work.

This idea seems in its very basic form, so I know you may be thinking stuff you've not included, or this may be as far as you've got so far, but those are some of my thoughts on the basic idea. Humanoid is not always the best choice, why is it watching humanity, and making it seem less like a God (immortal, glowing and watching over humanity) may be a good idea. Maybe focus on the story behind the object first before trying to make it take some form.

The entity usually takes forms of its own desire, and has lived to assume a human form. It usually visits some planets as a tour, just to get a first hand experience of the landscape.

It is a astral being, which people have reported seeing in their astral projection experiences. This astral being has ascended to our world and is constantly gaining intelligence of celestial information of the world it is in, but however, when it left its astral home, it forgot its knowledge of the entire astral world, which is what causes him, to not know who or what he is, which resulted in the glowing entity giving itself its own purpose. It uses the abilities it has, to survey sapient lifeforms.